This time I found the shuttle wait times a little long. I observed that SFO Park (green vans) and Anza had more frequent shuttles for the return leg of the trip.
I like the ease of parking at the lot and taking the shuttle to and from the airport. The shuttle is normally very timely but this trip, it was not the usual expectation. I arrived at 4:15am, and I was told that the shuttle was at the airport, and as soon as the driver came back, he would head to my car. I waited at least 25 minutes before the driver who came on at 4:30am headed over to where I was parked. He told me that the previous driver decided to stop for gas on the way back, and he didn't start his shift until 4:30. I'm glad that I always arrive earlier than needed for my flights, so this did not impact me at all. However, just something to be aware of in the future!